What is rimmed steel plate?
Rimmed steel plate is a hot rolled steel plate made of common carbon structural steel. Rimmed steel is a kind of steel with incomplete deoxygenation. Only a certain amount of weak deoxidizer is used to deoxidize liquid steel, which has high oxygen content. When molten steel is injected into the ingot mold, the carbon and oxygen reaction produces a large amount of gas, resulting in the boiling of liquid steel.
The carbon content of rimmed steel is low. Because of the lack of ferrosilicon deoxidation, the silicon content in steel is also low (Si< 0.07%). The outer layer of rimmed steel is crystallized under the condition of intense agitation of liquid steel caused by rimming, so the outside surface is pure, dense, with good surface quality, good plasticity and stamping performance.No large concentrated shrinkage hole, less cutting head, high yield, and the production process of rimmed steel is simple, less ferroalloy consumption, low steel cost.
Rimmed steel plate is widely used to manufacture all kinds of stamping parts, construction and engineering structures and some less important machine structure parts. However, there are more impurities in the core of the boiling steel, and the segregation is serious, the structure is not dense, and the mechanical properties are not uniform. At the same time, due to the high gas content in the steel, the toughness is low, the cold brittle and aging sensitivity is greater, and the welding performance is also poor. Therefore, rimmed steel plate is not suitable for manufacturing welding structures and other important structures that bear impact load and work at low temperature.